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What happens to my beer if my OG is higher? Maltier, richer, more full bodied beer compared to OG that is much less than a target resulting in lighter bodied beers?

This is a common misconception that I think causes a lot of brewers to go overboard with creating bigger and bigger beers. OG really doesn't have anything to do with the body or mouthfeel of a beer. You can have rich, malty beers with low OGs just as easily as you can find high gravity beers that are light and dry. For example, an Irish dry stout with an OG of 1.038 will be creamy and full-bodied compared to a Belgian tripel with an OG in the 1.070's.

The good news is that now that you're starting to do some of your own mashing, you can control the amount of unfermentables in your wort so that you can create a beer that falls anywhere in the spectrum. The basic idea is that if you mash at high temperatures for short periods of time, you'll get more unfermentables and raise your FG while lowering your ABV. If you want to do the opposite, mash for a longer time at a lower temperature.

This is a common misconception that I think causes a lot of brewers to go overboard with creating bigger and bigger beers. [...] The basic idea is that if you mash at high temperatures for short periods of time, you'll get more unfermentables and raise your FG while lowering your ABV. If you want to do the opposite, mash for a longer time at a lower temperature.

Thanks for sharing this. I haven't done much, if any, reading on mashing and temperatures but I will apply this method in my partial mash this next week as I am brewing a (hopefully) very creamy sweet stout.